Fig. 6

Mean (± SE) changes (Δ) in physiological variables in Lidia cows relative to baseline (0 h) following a change in the Temperature–Humidity Index (THI) category. Panels show (A) body temperature, (B) heart rate, (C) SDNN, and (D) RMSSD, recorded by subcutaneous biologgers under natural conditions in summer. Vertical dashed lines indicate the moment of the change in the THI category